One kick ass anime show.
Based on Vampires and Humans.
Started airing in 2008 but has yet to air in the US, meanwhile airing in TV Tokyo.

The plot line consist on a school. Which there's day-school (Humans) and night-school (Vampires).

Yūki is a adoptive daughter of the headmaster of Cross Academy and a perfect (Guardian) that protects the day-school humans from the night-school vampires.
Afterwords she falls in love with her friend Kaname who is a vampire and Zero.

Kaname: Pure blooded Vampire, pretty hooooot ^^

Zero: lost his parents from a pure blooded vampire so was also adopted by the headmaster of Cross Academy and a perfect (Guardian). Falls in love with Yūki but was bitten by a pure blood. Yūki doesn't know. He's not a pure blood yet but a half vampire/ half human.

Level E: When you're turn into a pure blooded Vampire.

Although they do attend the same school, the Vampires do not attack the Humans, they take tablets to calm their fetishes.

A recent vampire anime consisting characters named Kuran Kaname, Yuuki Cross, Zero Kiryuu, Shiki Senri, Hanabusa Aidou, and many more. This mostly takes place in an academy with night-classes for the vamps, and day-classes for the humans. Many of the day-class students are extremely obsessed with the night-class students. But little do they know, they are all vampires.

Yuuki is a prefect, or guardian in the academy. She sometimes finds some scary vampires, known as a Level E, wanting to ingest all her blood and kill her.

Characters:
Kaname Kuran = savior of Yuuki when she was a little girl. Also, Yuuki's crush.
Zero Kiryuu = vampire hunter and whose duty is to protect Yuuki, and vice versa.
And then, there are many other characters, mostly vampires. So yeah.. this is just a very small amount of detail of the show... So...